TY - JOUR

T1 - Structural Features of Polymer Ligand Environments Dramatically Affect the Mechanical and Room-Temperature Self-Healing Properties of Cobalt(II)-Incorporating Polysiloxanes

AU - Deriabin, Konstantin V.

AU - Ignatova, Nina A.

AU - Kirichenko, Sergey O.

AU - Novikov, Alexander S.

AU - Kryukova, Mariya A.

AU - Kukushkin, Vadim Yu

AU - Islamova, Regina M.

N1 - Publisher Copyright: ©

PY - 2021/8/9

Y1 - 2021/8/9

N2 - Cobalt(II)-pyridinedicarboxamide-co-polydimethylsiloxane (Co-Py-PDMSs) and cobalt(II)-bipyridinedicarboxamide-co-polydimethylsiloxane (Co-Bipy-PDMSs) polymer-metal complexes were prepared by complexation between Py-PDMSs or Bipy-PDMSs ligands and cobalt(II); the metal content in these complexes varied from 0.09 to 2.41 wt %. The CoII binding patterns (the Co-NPy and Co-O coordination in Co-Py-PDMSs and Co-NBipy in Co-Bipy-PDMSs) were established by UV-vis and IR methods and by comparison with model CoII complexes exhibiting relevant O,N,O- and N,N-coordination environments, respectively. The mechanical properties of the polymer-metal complexes were controlled by the coordination of Py-PDMSs or Bipy-PDMSs to CoII at various metal-to-ligand molar ratios (1:(1-6)) and by the variation of the polydimethylsiloxane unit length (Mn: 850-900, 5000, or 25 »000 g·mol-1). Utilization of the chelated Py-PDMSs and Bipy-PDMSs polymer ligands, which are capable of tri- or bidentate binding of CoII, led to (2-4)-fold increases in tensile strength (up to 1.75 MPa) and much higher elongation at break ((2-3)-fold increase up to 2100%) compared with the previously reported CoII-based polymer-ligand systems featuring monodentate ligation entities. Changing the main-chain ligand from Py-PDMSs to Bipy-PDMSs led to an increase in tensile strength of (2-4)-fold in comparison with Py-PDMS and a lower hysteresis (4%). The room temperature self-healing efficiency was up to 96% for Co-Py-PDMSs and 40% for Co-Bipy-PDMSs, as measured for a polydimethylsiloxane unit with Mn = 25 »000 g·mol-1.

AB - Cobalt(II)-pyridinedicarboxamide-co-polydimethylsiloxane (Co-Py-PDMSs) and cobalt(II)-bipyridinedicarboxamide-co-polydimethylsiloxane (Co-Bipy-PDMSs) polymer-metal complexes were prepared by complexation between Py-PDMSs or Bipy-PDMSs ligands and cobalt(II); the metal content in these complexes varied from 0.09 to 2.41 wt %. The CoII binding patterns (the Co-NPy and Co-O coordination in Co-Py-PDMSs and Co-NBipy in Co-Bipy-PDMSs) were established by UV-vis and IR methods and by comparison with model CoII complexes exhibiting relevant O,N,O- and N,N-coordination environments, respectively. The mechanical properties of the polymer-metal complexes were controlled by the coordination of Py-PDMSs or Bipy-PDMSs to CoII at various metal-to-ligand molar ratios (1:(1-6)) and by the variation of the polydimethylsiloxane unit length (Mn: 850-900, 5000, or 25 »000 g·mol-1). Utilization of the chelated Py-PDMSs and Bipy-PDMSs polymer ligands, which are capable of tri- or bidentate binding of CoII, led to (2-4)-fold increases in tensile strength (up to 1.75 MPa) and much higher elongation at break ((2-3)-fold increase up to 2100%) compared with the previously reported CoII-based polymer-ligand systems featuring monodentate ligation entities. Changing the main-chain ligand from Py-PDMSs to Bipy-PDMSs led to an increase in tensile strength of (2-4)-fold in comparison with Py-PDMS and a lower hysteresis (4%). The room temperature self-healing efficiency was up to 96% for Co-Py-PDMSs and 40% for Co-Bipy-PDMSs, as measured for a polydimethylsiloxane unit with Mn = 25 »000 g·mol-1.

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UR - http://www.scopus.com/inward/record.url?scp=85112724413&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/0ec2056c-5789-359b-8efb-b94fc95ba041/

U2 - 10.1021/acs.organomet.1c00392

DO - 10.1021/acs.organomet.1c00392

M3 - Article

AN - SCOPUS:85112724413

VL - 40

SP - 2750

EP - 2760

JO - Organometallics

JF - Organometallics

SN - 0276-7333

IS - 15

ER -